The overall goal of this research is to obtain a detailed description of the organization of ribonucleoprotein (RNP) complexes associated with specific nuclear RNA molecules. HeLa cells productively infected with human adenovirus 2 (ad2) will be used for this study because transcription and processing of adenovirus RNA are relatively well understood and transcripts of adenovirus are highly abundant in the cell nucleus at late infection. Initial studies indicate that RNA molecules transcribed from the ad2 genome are tightly associated with proteins in the cell nucleus in specific RNP complexes. Further experiments will focus on the possible relationship between the nucleotide sequence of adenovirus RNA and the sites of protein-RNA interactions. This relationship will be examined by digesting RNA in nuclear complexes with nuclease, isolating RNA and characterizing the protected regions of RNA by hybridization to specific DNA restriction fragments of the adenovirus genome.